PROJECT SUMMARY I am an environmental epidemiologist with primary research interests in the role of early-life chemical exposures on the immune and respiratory systems. The goal of this proposal is to obtain skills needed to further my postdoctoral training in examining early-life chemical exposures and child allergic, respiratory, and immune outcomes. Linking chemical exposures and allergic disease development is important to improve our understanding of modifiable risk factors for childhood atopic diseases, including eczema and asthma. Formal coursework and expert mentorship from Drs. Joseph Braun, Adam Spanier, and George Papandonatos will enable me to acquire the knowledge, skills, and abilities to achieve my long-term career goal of becoming an independent researcher. This training will allow me to pursue independent research aims examining the impact of triclosan exposures on wheeze, eczema, and asthma risks using longitudinal exposure and outcome data in an ongoing cohort. All relevant exposure, covariate, and outcome were previously collected as part of the NIH- funded Health Outcomes and Measures of the Environment (HOME) Study, an ongoing pregnancy and birth cohort study. The primary objectives of this proposal are to rigorously characterize associations of gestational and early-childhood exposure to triclosan with eczema and asthma outcomes in order to identify potential windows of allergic and/or respiratory health susceptibility from triclosan exposure. Specifically, I will 1) train in biomarkers of gestational and childhood triclosan exposure and advanced epidemiologic methods to measure their impacts with Dr. Braun, 2) learn advanced statistical skills with Drs. Papandonatos and Braun: a) in longitudinal and repeated measures analyses to characterize patterns and trajectories of eczema and wheeze, b) to identify susceptible windows to enhance our ability to detect effects and c) to identify vulnerable groups, 3) train in early-childhood allergy development, airway inflammation, and child lung development and physiology with Dr. Spanier, and 4) translate my research and training to position myself for a future K-award. This proposal will address gaps in the understanding of the timing through which triclosan exposure may affect allergic disease development in children. This proposed research and training plan lays the foundation for my independent research career that aims to clarify how early-life exposures to environmental chemicals may be important determinants of asthma and other allergic disease development and the potential biological mechanisms through which they may act.